BL 7.5 inch Mk VI naval gun
Encyclopedia
The BL 7.5 inch gun Mark VI was the 45 calibre naval gun forming the main battery of Royal Navy
s. These ships with seven single gun mounts were significant to the cruiser
limitations defined by the Washington Naval Treaty
.
s with two tubes, full-length wire winding, a jacket, and Welin breech block
with hand operated Asbury mechanism. They used two cloth bags each containing 14 kg (31 pounds) of cordite
to fire a 200-pound (91-kg) projectile up to 19 kilometers at their maximum elevation of 30 degrees. Useful life expectancy was 650 effective full charges (EFC) per barrel.
in the Netherlands Antilles
, five in Mozambique
, three in Canada
, and three in a battery at South Shields
during the Second World War.
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...
s. These ships with seven single gun mounts were significant to the cruiser
Cruiser
A cruiser is a type of warship. The term has been in use for several hundreds of years, and has had different meanings throughout this period...
limitations defined by the Washington Naval Treaty
Washington Naval Treaty
The Washington Naval Treaty, also known as the Five-Power Treaty, was an attempt to cap and limit, and "prevent 'further' costly escalation" of the naval arms race that had begun after World War I between various International powers, each of which had significant naval fleets. The treaty was...
.
Description
These were built-up gunBuilt-up gun
The term built-up gun describes a construction technique for artillery barrels. An inner tube of metal which stretches most within its elastic limit enlarges under the pressure of confined powder gases to transmit stress to outer cylinders under tension...
s with two tubes, full-length wire winding, a jacket, and Welin breech block
Welin breech block
The Welin breech block was a revolutionary stepped, interrupted thread design for locking artillery breeches, invented by Axel Welin in 1889 or 1890...
with hand operated Asbury mechanism. They used two cloth bags each containing 14 kg (31 pounds) of cordite
Cordite
Cordite is a family of smokeless propellants developed and produced in the United Kingdom from 1889 to replace gunpowder as a military propellant. Like gunpowder, cordite is classified as a low explosive because of its slow burning rates and consequently low brisance...
to fire a 200-pound (91-kg) projectile up to 19 kilometers at their maximum elevation of 30 degrees. Useful life expectancy was 650 effective full charges (EFC) per barrel.
Coast defence guns
Seven guns were installed as coastal artilleryCoastal artillery
Coastal artillery is the branch of armed forces concerned with operating anti-ship artillery or fixed gun batteries in coastal fortifications....
in the Netherlands Antilles
Netherlands Antilles
The Netherlands Antilles , also referred to informally as the Dutch Antilles, was an autonomous Caribbean country within the Kingdom of the Netherlands, consisting of two groups of islands in the Lesser Antilles: Aruba, Bonaire and Curaçao , in Leeward Antilles just off the Venezuelan coast; and Sint...
, five in Mozambique
Mozambique
Mozambique, officially the Republic of Mozambique , is a country in southeastern Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi and Zambia to the northwest, Zimbabwe to the west and Swaziland and South Africa to the southwest...
, three in Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, and three in a battery at South Shields
South Shields
South Shields is a coastal town in Tyne and Wear, England, located at the mouth of the River Tyne to Tyne Dock, and about downstream from Newcastle upon Tyne...
during the Second World War.
Shell trajectory
| Range | Elevation | Time of flight | Descent | Impact velocity |
|---|---|---|---|---|
| 5000 yd (4.6 km) | 2° 30′ | 7 sec | 3° 19′ | 1799 ft/s (548 m/s) |
| 10000 yd (9.1 km) | 7° 3′ | 17 sec | 12° 32′ | 1218 ft/s (371 m/s) |
| 15000 yd (14 km) | 15° 21′ | 32 sec | 27° 33′ | 1038 ft/s (316 m/s) |
| 20000 yd (18 km) | 27° 59′ | 51 sec | 44° 35′ | 1071 ft/s (326 m/s) |
See also
- List of naval guns
- BL 7.5 inch Mk II - V naval gunBL 7.5 inch Mk II - V naval gunThe BL 7.5 inch guns Mk II - Mk V were a variety of 50 calibres naval guns used by Britain in World War I. They all had similar performance and fired the same shells.-Mark II:...
(earlier Royal Navy guns of the same caliber) - BL 8 inch Mk VIII naval gunBL 8 inch Mk VIII naval gunThe 50 calibre BL 8 inch gun Mark VIII was the main battery gun used on the Royal Navy's County-class heavy cruisers, in compliance with the Washington Naval Treaty of 1922. This treaty allowed ships of not more than 10,000 tons standard displacement and with guns no larger than 8 inches to be...
(used on subsequent Royal Navy heavy cruisers)
External links
- Tony DiGiulain, Britain 7.5"/45 (19 cm) Mark VI